package com.mframe.util;
import java.security.*;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;

/**
 *Title: Des加解密 <br/>
 *Description: Des加解密<br/>
 *Copyright (c) 2011 ICSS HaiSheng Co.,Ltd <br/>
 *All Rights Reserved<br/>
 *author youjx <br/>
 *Create Date:2011-05-11 <br/>
 *Modify By:修改人 <br/>
 *Modify Date:修改日期 <br/>
 *Remark:修改说明<br/>
 **/

public class Encrypt {

	private static final String PASSWORD_CRYPT_KEY = "ppkk!99de1920xmnw"; // 加密密码
	private final static String DES = "DES"; // DES串

	/**
	 * function:加密<br/>
	 * remark:
	 * 
	 * @param src
	 *            数据源
	 * @param key
	 *            密钥，长度必须是8的倍数
	 * @return 返回加密后的数据
	 * @throws Exception
	 **/
	public static byte[] encrypt(byte[] src, byte[] key) throws Exception {
		// DES算法要求有一个可信任的随机数源
		SecureRandom sr = new SecureRandom();

		// 从原始密匙数据创建DESKeySpec对象
		DESKeySpec dks = new DESKeySpec(key);
		// 创建一个密匙工厂，然后用它把DESKeySpec转换成
		// 一个SecretKey对象
		SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
		SecretKey securekey = keyFactory.generateSecret(dks);
		// Cipher对象实际完成加密操作
		Cipher cipher = Cipher.getInstance(DES);
		// 用密匙初始化Cipher对象
		cipher.init(Cipher.ENCRYPT_MODE, securekey, sr);
		// 现在，获取数据并加密
		// 正式执行加密操作
		return cipher.doFinal(src);
	}

	/**
	 * function:解密<br/>
	 * remark:
	 * 
	 * @param src
	 *            数据源
	 * @param key
	 *            密钥，长度必须是8的倍数
	 * @return 返回解密后的原始数据
	 * @throws Exception
	 **/
	public static byte[] decrypt(byte[] src, byte[] key) throws Exception {
		// DES算法要求有一个可信任的随机数源
		SecureRandom sr = new SecureRandom();
		// 从原始密匙数据创建一个DESKeySpec对象
		DESKeySpec dks = new DESKeySpec(key);
		// 创建一个密匙工厂，然后用它把DESKeySpec对象转换成
		// 一个SecretKey对象
		SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
		SecretKey securekey = keyFactory.generateSecret(dks);
		// Cipher对象实际完成解密操作
		Cipher cipher = Cipher.getInstance(DES);
		// 用密匙初始化Cipher对象
		cipher.init(Cipher.DECRYPT_MODE, securekey, sr);
		// 现在，获取数据并解密
		// 正式执行解密操作
		return cipher.doFinal(src);
	}

	/**
	 * function:密码解密<br/>
	 * remark:
	 * 
	 * @param data
	 *            加密后的数据
	 * @return String 解密后的数据
	 * @throws Exception
	 **/
	public final static String decrypt(String data) {
		try {
			return new String(decrypt(hex2byte(data.getBytes()),
					PASSWORD_CRYPT_KEY.getBytes()));
			// return new
			// String(decrypt(hex2byte(data.getBytes()),PASSWORD_CRYPT_KEY.getBytes()),"GB2312");
		} catch (Exception e) {
		}
		return null;
	}

	/**
	 * function:密码加密<br/>
	 * remark:
	 * 
	 * @param password
	 * @return String
	 * @throws Exception
	 **/
	public final static String encrypt(String password) {
		try {
			String strc = password;
			strc = new String(strc.getBytes("GB2312"));
			return byte2hex(encrypt(password.getBytes(), PASSWORD_CRYPT_KEY
					.getBytes()));
			// return
			// byte2hex(encrypt(strc.getBytes(),PASSWORD_CRYPT_KEY.getBytes()));
		} catch (Exception e) {
		}
		return null;
	}

	public static String byte2hex(byte[] b) {

		String hs = "";

		String stmp = "";

		for (int n = 0; n < b.length; n++) {

			stmp = (java.lang.Integer.toHexString(b[n] & 0XFF));

			if (stmp.length() == 1)

				hs = hs + "0" + stmp;

			else

				hs = hs + stmp;

		}

		return hs.toUpperCase();

	}

	public static byte[] hex2byte(byte[] b) {

		if ((b.length % 2) != 0)

			throw new IllegalArgumentException("长度不是偶数");

		byte[] b2 = new byte[b.length / 2];

		for (int n = 0; n < b.length; n += 2) {

			String item = new String(b, n, 2);

			b2[n / 2] = (byte) Integer.parseInt(item, 16);

		}

		return b2;
	}
	
	
	
}